-
Notifications
You must be signed in to change notification settings - Fork 2
/
apb_model.py
221 lines (170 loc) · 5.87 KB
/
apb_model.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
import math
from hwtypes import Enum, Product, Bit, BitVector
import apb
from functools import lru_cache, wraps
import inspect
def canonicalize_args(f):
"""Wrapper for functools.lru_cache() to canonicalize default
and keyword arguments so cache hits are maximized."""
@wraps(f)
def wrapper(*args, **kwargs):
sig = inspect.getfullargspec(f.__wrapped__)
# build newargs by filling in defaults, args, kwargs
newargs = [None] * len(sig.args)
if sig.defaults is not None:
newargs[-len(sig.defaults):] = sig.defaults
newargs[:len(args)] = args
for name, value in kwargs.items():
newargs[sig.args.index(name)] = value
return f(*newargs)
return wrapper
class APBCommand(Enum):
READ = 0
WRITE = 1
IDLE = 2
@canonicalize_args
@lru_cache(maxsize=None)
def APB(addr_width, data_width, num_slaves=1):
strobe_width = math.ceil(data_width / 8)
fields = {
"PADDR": BitVector[addr_width],
"PWRITE": Bit,
}
for i in range(num_slaves):
fields[f"PSEL{i}"] = Bit
fields.update({
"PENABLE": Bit,
"PWDATA": BitVector[data_width],
"PRDATA": BitVector[data_width],
"PREADY": Bit,
"PSTRB": BitVector[strobe_width],
"PPROT": Bit,
"SLVERR": Bit,
})
result = type("_APB", (Product, ), fields)
return result
def default_APB_instance(_APB):
"""
Convenience function to instantiate an _APB object with default values of 0
"""
fields = {}
for key, value in _APB.field_dict.items():
fields[key] = value(0)
return _APB(**fields)
@canonicalize_args
@lru_cache(maxsize=None)
def Request(addr_width, data_width, num_slaves):
class _Request(Product):
command = APBCommand
address = BitVector[addr_width]
data = BitVector[data_width]
slave_id = BitVector[max(math.ceil(math.log2(num_slaves)), 1)]
return _Request
@canonicalize_args
@lru_cache(maxsize=None)
def APBBusIO(addr_width, data_width, num_slaves=1):
class IO(Product):
apb = APB(addr_width, data_width, num_slaves)
request = Request(addr_width, data_width, num_slaves)
return IO
@canonicalize_args
@lru_cache(maxsize=None)
def APBBus(addr_width, data_width, num_slaves=1):
class APBBus:
def __init__(self):
self.IO = APBBusIO(addr_width, data_width, num_slaves)
# TODO: Move main logic to a base class
self.main = self._main()
next(self.main)
def __call__(self, io):
self.io = io
self.main.send(None)
def _main(self):
yield
while True:
if self.io.request.command == APBCommand.READ:
yield from self.read(self.io.request.address,
self.io.request.data)
elif self.io.request.command == APBCommand.WRITE:
yield from self.write(self.io.request.address,
self.io.request.data)
else:
yield
def set_psel(self, value):
setattr(self.io.apb, f"PSEL{self.io.request.slave_id}", value)
def write(self, address, data):
self.io.apb.PADDR = address
self.io.apb.PWDATA = data
self.set_psel(Bit(1))
self.io.apb.PWRITE = Bit(1)
yield
self.io.apb.PENABLE = Bit(1)
yield
while not self.io.apb.PREADY:
# TODO: Insert timeout logic
yield
self.io.apb.PENABLE = Bit(0)
self.set_psel(Bit(0))
def read(self, address, data):
self.io.apb.PADDR = address
self.set_psel(Bit(1))
self.io.apb.PWRITE = Bit(0)
yield
self.io.apb.PENABLE = Bit(1)
yield
while not self.io.apb.PREADY:
# TODO: Insert timeout logic
yield
self.io.apb.PENABLE = Bit(0)
self.set_psel(Bit(0))
# TODO: Handle PSLVERR and checking the expected data
return APBBus()
def set_apb_inputs(tester, bus):
for key in tester._circuit.apb.keys():
# Skip clock signals
if key in ["PCLK", "PRESETn"]:
continue
if tester._circuit.apb[key].is_output():
setattr(tester.circuit.apb, key,
getattr(bus.io.apb, key))
def make_request(addr, data, addr_width, data_width, num_slaves=1, slave_id=0):
request = Request(addr_width, data_width, num_slaves)(
APBCommand.IDLE, BitVector[addr_width](addr),
BitVector[data_width](data),
BitVector[max(math.ceil(math.log2(num_slaves)), 1)](slave_id))
# Specialized instance of APB for addr/data width
_APB = APB(addr_width, data_width, num_slaves)
io = APBBusIO(addr_width, data_width,
num_slaves)(default_APB_instance(_APB), request)
return io, request
def step(bus, io, tester):
bus(io)
set_apb_inputs(tester, bus)
tester.step(2)
def write(bus, io, request, tester, addr, data):
# Test idle state
step(bus, io, tester)
# Send request
request.command = APBCommand.WRITE
step(bus, io, tester)
request.command = APBCommand.IDLE
# No wait state
io.apb.PREADY = Bit(1)
step(bus, io, tester)
tester.circuit.apb.PREADY.expect(1)
step(bus, io, tester)
tester.circuit.apb.PREADY.expect(0)
tester.step(2)
def read(bus, io, request, tester, addr, data):
# Send request
request.command = APBCommand.READ
step(bus, io, tester)
request.command = APBCommand.IDLE
# No wait state
io.apb.PREADY = Bit(1)
step(bus, io, tester)
tester.circuit.apb.PREADY.expect(1)
tester.circuit.apb.PRDATA.expect(data)
step(bus, io, tester)
tester.circuit.apb.PREADY.expect(0)
tester.step(2)